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7. Audio Volume
Check Q851,
NO
Q852, IC850
and J851.
Is
digital signal
output from
IC702"7"?
YES
Is
digital signal output
from IC701"20"?
YES
Is digital
signal output from
IC702"10", "13", "16"
and "19"?
YES
Check IC703, IC704
and their periphery.
supplied correctly
to each IC?
signal output
from J701 (pin
YES
Is sound
output from
output from
headphone?
headphone?
YES
Check Q705,
OK
Q706 and J701
(soldered part).
NO
Check IC702
and PLL.
NO
Replace
IC701.
NO
Replace
IC702.
Power
NO
to Power Supply
YES
*
IC701 and IC702 are supplied
power from IC705.
Check I/O voltage of IC705.
Is sound
jack)?
NO
Is sound
NO
Q707 collector at
YES
digital signal output
from IC701"5", "6" and
digital signal output from
IC701"18" and "19"
* PLL normal lock voltage
Between TP701 and TP702.
When fs=44.1kHz
When fs=48kHz
When fs=96kHz
*
Changing over the cutoff frequency of analog LPF
When fs=44.1kHz or 48kHz,
Microcomputer port FS2 is at the "L" level,
and Q703 and Q704 are turned ON.
When fs=96kHz,
Microcomputer port FS2 is at the "H" level,
and Q703 and Q704 are turned OFF.
Volume
Approx
. 5V
Voltage of
Check Q913 and
NO
Q946 of muting
-10V?
YES
Is
Check according to
NO
the signal flow for
"7"?
YES
Is
NO
?
YES
0.6V
0.9V
2.6V
drive circuit.
main CB.
Replace IC701.
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